/********************first_drv.c************************/
 
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <asm/uaccess.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <mach/regs-gpio.h>
#include <mach/hardware.h>
#include <linux/device.h>
 
static struct class *firstdrv_class;
static struct class_device	*firstdrv_class_dev;
 
volatile unsigned long *gpfcon = NULL;
volatile unsigned long *gpfdat = NULL;
 
 
static int first_drv_open(struct inode *inode, struct file *file)
{
	//printk("first_drv_open\n");
	/* 配置GPF4,5,6为输出 */
	*gpfcon &= ~((0x3<<(4*2)) | (0x3<<(5*2)) | (0x3<<(6*2)));
	*gpfcon |= ((0x1<<(4*2)) | (0x1<<(5*2)) | (0x1<<(6*2)));
	return 0;
}
 
static ssize_t first_drv_write(struct file *file, const char __user *buf, size_t count, loff_t * ppos)
{
	int val;
 
	//printk("first_drv_write\n");
 
	copy_from_user(&val, buf, count); //	copy_to_user();
 
	if (val == 1)
	{
		// 点灯
		*gpfdat &= ~((1<<4) | (1<<5) | (1<<6));
	}
	else
	{
		// 灭灯
		*gpfdat |= (1<<4) | (1<<5) | (1<<6);
	}
	
	return 0;
}
 
static struct file_operations first_drv_fops = {
    .owner  =   THIS_MODULE,    /* 这是一个宏，推向编译模块时自动创建的__this_module变量 */
    .open   =   first_drv_open,     
	.write	=	first_drv_write,	   
};
 
 
int major;
static int first_drv_init(void)
{
	major = register_chrdev(0, "first_drv", &first_drv_fops); // 注册, 告诉内核，并且自动分配主设备号为major
 
	firstdrv_class = class_create(THIS_MODULE, "firstdrv"); 
   if(IS_ERR(firstdrv_class)){
     printk(KERN_INFO"creat class error\n");
     return -1;
   }
 
	firstdrv_class_dev = device_create(firstdrv_class, NULL, MKDEV(major, 0), NULL, "myled"); /* /dev/xyz */
 
	gpfcon = (volatile unsigned long *)ioremap(0x56000050, 16);  //地址映射：从0x56000050开始的16个字节的内存映射到gpfcon
	gpfdat = gpfcon + 1;
 
	return 0;
}
 
static void first_drv_exit(void)
{
	unregister_chrdev(major, "first_drv"); // 卸载
 
	device_unregister(firstdrv_class_dev);
	class_destroy(firstdrv_class);
	iounmap(gpfcon);//地址映射：从0x56000050开始的16个字节对应的指针gpfcon使用结束，不在通过此指针操作这片内存
}
 
module_init(first_drv_init);
module_exit(first_drv_exit);
 
 
MODULE_LICENSE("GPL");
 